Phlox plant named ‘USPLX50302’

ABSTRACT

A new and distinct cultivar of  Phlox  plant named ‘USPLX50302’, characterized by its upright, outwardly spreading and mounding plant form; vigorous growth habit; freely branching habit and short internodes; dense and busy plant habit; freely and continuous flowering habit; white-colored flowers; relatively tolerant to high temperatures; and relatively resistant to Powdery Mildew.

Botanical designation: Phlox hybrida.

Cultivar denomination: ‘USPLX50302’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Phlox plant, botanically known as Phlox hybrida and hereinafter referred to by the name ‘USPLX50302’.

The new Phlox plant is a product of a planned breeding program conducted by the Inventor in Higashiomi, Shiga, Japan and Bonsall, Calif. The objective of the breeding program is to create new uniformly mounding Phlox plants with unique flower color and resistance to Powdery Mildew.

The new Phlox plant originated from a cross-pollination made by the Inventor on Jun. 12, 2005 in Higashiomi, Shiga, Japan of an unnamed selection of Phlox glabriflora, not patented, as the female, or seed, parent with an unnamed seedling selection of Phlox hybrida, not patented, as the male, or pollen, parent. The new Phlox plant was discovered and selected by the Inventor as a single flowering plant within the progeny of the stated cross-pollination in a controlled environment in Bonsall, Calif. on Jul. 6, 2006.

Asexual reproduction of the new Phlox plant by cuttings in a controlled environment in Bonsall, Calif. since Jul. 10, 2006, has shown that the unique features of this new Phlox plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Phlox plant have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment and cultural practices such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘USPLX50302’. These characteristics in combination distinguish ‘USPLX50302’ as a new and distinct cultivar of Phlox:

-   -   1. Upright, outwardly spreading and mounding plant form.     -   2. Vigorous growth habit.     -   3. Freely branching habit and short internodes; dense and busy         plant habit.     -   4. Freely and continuous flowering habit.     -   5. White-colored flowers.     -   6. Relatively tolerant to high temperatures.     -   7. Relatively resistant to Powdery Mildew.

Plants of the new Phlox can be compared to plants of the parent selections. Plants of the new Phlox differ from plants of the female parent selection in the following characteristics:

-   -   1. Plants of the new Phlox are more freely branching than plants         of the female parent selection.     -   2. Plants of the new Phlox are more mounding than and not as         creeping as plants of the female parent selection.

Plants of the new Phlox differ primarily from plants of the male parent selection in plant vigor as plants of the new Phlox are more vigorous than plants of the male parent selection.

Plants of the new Phlox can be compared to plants of the Phlox ‘USPHLOTM6’, disclosed in U.S. Plant Pat. No. 17,797. In side-by-side comparisons, plants of the new Phlox and ‘USPHLOTM6’ differed in the following characteristics:

-   -   1. Plants of the new Phlox were more compact than plants of         ‘USPHLOTM6’.     -   2. Plants of the new Phlox were more freely branching than         plants of ‘USPHLOTM6’.     -   3. Flower petals of plants of the new Phlox were more serrated         and pointed than flower petals of plants of ‘USPHLOTM6’.

Plants of the new Phlox can also be compared to plants of the Phlox ‘Snow Crisp’, not patented. In side-by-side comparisons, plants of the new Phlox and ‘Snow Crisp’ differed in the following characteristics:

-   -   1. Plants of the new Phlox were more vigorous than plants of         ‘Snow Crisp’.     -   2. Flower petals of plants of the new Phlox were more serrated         and pointed than flower petals of plants of ‘Snow Crisp’.     -   3. Plants of the new Phlox were more resistant to Powdery Mildew         than plants of ‘Snow Crisp’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearance of the new Phlox plant, showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Phlox plant.

The photograph at the bottom of the sheet comprises a side perspective view of a typical flowering plant of ‘USPLX50302’ grown in a container.

The photograph at the top of the sheet is a close-up view of typical flowers and leaves of ‘USPLX50302’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurements and values describe plants grown in Bonsall, Calif., under commercial practice in one-gallon containers during the autumn in an outdoor nursery with day temperatures ranging from 18° C. to 38° C., night temperatures ranging from 9° C. to 18° C. and light levels ranging from 7,000 to 10,000 foot-candles. Plants were pinched one time and were ten weeks old when the photographs and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 2007 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Phlox hybrida ‘USPLX50302’. -   Parentage:     -   -   Female, or seed, parent.—Unnamed selection of Phlox             glabriflora, not patented.         -   Male, or pollen, parent.—Unnamed seedling selection of Phlox             hybrida, not patented. -   Propagation:     -   -   Type.—By cuttings.         -   Time to initiate roots, summer.—About six days at             temperatures ranging from 17° C. to 29° C.         -   Time to initiate roots, winter.—About four days at             temperatures ranging from 17° C. to 21° C.         -   Time to produce a rooted plant, summer.—About 28 days at             temperatures ranging from 17° C. to 29° C.         -   Time to produce a rooted plant, winter.—About 25 days at             temperatures ranging from 17° C. to 21° C.         -   Root description.—Thin to medium in thickness; white in             color.         -   Rooting habit.—Moderate branching; sparse to medium in             density. -   Plant description:     -   -   Plant form/habit.—Upright, outwardly spreading and mounding             plant form; vigorous growth habit; freely branching habit,             about seven main laterals each with numerous secondary             laterals; relatively short internodes; dense and bushy plant             habit.         -   Plant height.—About 20 cm.         -   Plant width (spread).—About 46 cm.         -   Lateral branches.—Length: About 29 cm. Diameter: About 2 mm.             Internode length: About 1.2 cm. Strength: Strong. Texture:             Pubescent. Color: Close to 146B. -   Foliage description:     -   -   Arrangement.—Alternate, simple; sessile.         -   Length.—About 3 cm.         -   Width.—About 7 mm.         -   Shape.—Oblong.         -   Apex.—Acute.         -   Base.—Rounded to slightly auriculate; clasping.         -   Margin.—Entire.         -   Texture, upper and lower surfaces.—Pubescent.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Close to 146A.             Developing leaves, lower surface: Close to 146B. Fully             expanded leaves, upper surface: Close to 146A; venation,             close to 146B. Fully expanded leaves, lower surface: Close             to 147B; venation, close to 146C. -   Flower description:     -   -   Flower type/habit.—Single rotate and salverform flowers             arranged in small cymes of four flowers each; flowers face             upright to outwardly; freely flowering habit with about 120             flower buds and flowers developing per plant.         -   Fragrance.—None detected.         -   Natural flowering season.—Continuously flowering from spring             to frost in California.         -   Postproduction longevity.—Flowers last about five days on             the plant; flowers persistent.         -   Flower buds.—Height: About 1.4 cm. Diameter: About 2.5 mm.             Shape: Narrowly elongate. Color: Close to 157A.         -   Inflorescence height.—About 2.5 cm.         -   Inflorescence diameter.—About 3.5 cm to 4 cm.         -   Flower diameter.—About 2.3 cm.         -   Flower depth.—About 1.8 cm.         -   Flower throat diameter.—About 1.5 mm.         -   Flower tube length.—About 1.4 cm.         -   Flower tube diameter, at base.—About 2 mm.         -   Petals.—Quantity per flower: Typically five in a single             whorl; petals fused at the base into a narrow tube. Lobe             length: About 1.2 cm. Lobe width: About 1.1 cm. Shape:             Obovate. Apex: Rounded with a shallow point. Margin: Entire.             Texture: Petal lobes, upper surface: Smooth, glabrous;             velvety. Petal lobes, lower surface: Smooth, glabrous;             satiny. Throat: Smooth, glabrous. Tube: Pubescent. Color:             Developing and fully expanded petals, upper surface: Close             to NN155A; venation, close to NN155A. Developing and fully             expanded petals, lower surface: Close to NN155C; venation,             close to NN155C. Flower throat: Close to 157A; venation,             close to 157A. Flower tube: Close to 157A; venation, close             to 157A.         -   Sepals.—Quantity per flower: Typically five in a single             whorl, fused towards the base into a slender tube and             reflexed towards the apex. Length: About 1 cm. Width: About             1 mm. Shape: Lanceolate. Apex: Acuminate. Margin: Entire.             Texture, upper and lower surfaces: Pubescent. Color, upper             surface: Close to 146A. Color, lower surface: Close to 146B.         -   Peduncles.—Length: About 1 cm. Diameter: About 1 mm. Angle:             Erect to about 45° from vertical. Strength: Strong. Texture:             Pubescent. Color: Close to 144B.         -   Pedicels.—Length: About 6 mm. Diameter: About 1 mm. Angle:             Erect to about 30° from peduncle axis. Strength: Strong.             Texture: Pubescent. Color: Close to 144B.         -   Reproductive organs.—Stamens: Quantity per flower: Typically             five. Filament length: About 1 mm. Filament color: Close to             157A. Anther shape: Narrowly oblong. Anther length: About             2 mm. Anther color: Close to 12A. Pollen amount: Scarce.             Pollen color: Close to 14A. Pistils: Quantity per flower:             One. Pistil length: About 5 mm. Stigma shape: Tri-parted.             Stigma color: Close to 157A. Style length: About 1.5 mm.             Style color: Close to 145D. Ovary color: Close to 144B.         -   Seed/fruit.—Seed and fruit development have not been             observed. -   Disease/pest resistance: Plants of the new Phlox have been noted to     be relatively resistant to Powdery Mildew. Plants of the new Phlox     have not been noted to be resistant to pests and other pathogens     common to Phlox. -   Garden performance: Plants of the new Phlox have been observed to     have good garden performance and tolerate rain, wind and     temperatures ranging from about 1° C. to about 40° C.; relatively     tolerant to high temperatures. 

1. A new and distinct Phlox plant named ‘USPLX50302’ as illustrated and described. 